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Standard anatomical terms of location are used to describe unambiguously the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on.
The origin of a muscle is the bone, typically proximal, which has greater mass and is more stable during a contraction than a muscle's insertion. [14] For example, with the latissimus dorsi muscle, the origin site is the torso, and the insertion is the arm. When this muscle contracts, normally the arm moves due to having less mass than the torso.
The gross anatomy of a muscle is the most important indicator of its role in the body. One particularly important aspect of gross anatomy of muscles is pennation or lack thereof. In most muscles, all the fibers are oriented in the same direction, running in a line from the origin to the insertion.
The discipline of anatomy can be subdivided into a number of branches, including gross or macroscopic anatomy and microscopic anatomy. [10] Gross anatomy is the study of structures large enough to be seen with the naked eye, and also includes superficial anatomy or surface anatomy, the study by sight of the external body features.
This glossary of biology terms is a list of definitions of fundamental terms and concepts used in biology, the study of life and of living organisms.It is intended as introductory material for novices; for more specific and technical definitions from sub-disciplines and related fields, see Glossary of cell biology, Glossary of genetics, Glossary of evolutionary biology, Glossary of ecology ...
Segmentation in biology is the division of some animal and plant body plans into a linear series of repetitive segments that may or may not be interconnected to each other. This article focuses on the segmentation of animal body plans, specifically using the examples of the taxa Arthropoda , Chordata , and Annelida .
Local adaptation is a mechanism in evolutionary biology whereby a population of organisms evolves to be more well-suited to its local environment than other members of the same species that live elsewhere. Local adaptation requires that different populations of the same species experience different natural selection. For example, if a species ...
For example, in a full tree of life, the entire clade of animals can be collapsed to a single branch of the tree. However, this is merely a limitation of rendering space. In theory, a true and complete tree for all living organisms or for any DNA sequence could be generated. [4] Nevertheless, phylogenies can sometimes appear in a non-treelike form.